Add high-level instructions for using BlueStacks

[yanokwa]

Install BlueStacks.

Settings > Display > Display resolution > Portrait (rebot)

Home button > System apps > Play Store

Login with Google account

Search for ODK Collect

Install

Configure with QR code

Import QR code > Pick From Mac/PC.

Use saved QR code (png) from app users in Central.

It will be in SM-G998B > DCIM > SharedFolder

Docs should go maybe here: https://docs.getodk.org/collect-mirror/